论文标题
桥接邦迪和事件地平线量表：3D GRMHD模拟显示X形射线星系形态
Bridging Bondi and Event Horizon Scales: 3D GRMHD Simulations Reveal X-Shaped Radio Galaxy Morphology
论文作者
论文摘要
X形射电星系（XRGS）产生未对准的X形喷射对，并组成$ \ Lessim10 \％$ $ $ $ $的射电星系。 XRG被认为会出现在带有二进制超级黑洞（$ \ rm smbh $），$ \ rm smbh $合并或大规模环境中等不对称的星系中。我们证明，如果没有这种特殊的，先前存在的条件，则可以自然形成XRG形态。我们的3D通用型磁性水力动力（GRMHD）首次模拟是从$ \ rm smbh $ smbh $ radius $ r _ {\ rm b} $的影响力的磁性旋转气体到$ \ rm rm smbh $ rm smbh $ grattitation $ r _ r _ r _ r _ r _ r _} $ r _ {\ rm b}/r _ {\ rm g} = 10^3 $到目前为止。最初，我们的恒定热气体的轴对称系统包含弱垂直磁场，并在快速旋转的$ \ rm SMBH $的赤道平面中旋转。我们用小规模$ 2 \％$ - 水平压力扰动播种气体。插入气体形成一个积聚磁盘，$ \ rm SMBH $启动相对磁性的准直喷，到达$ r _ {\ rm b} $之外。在插入气体的压力下，喷气机断断续续地打开和关闭，摇摆不定，并在不同方向上充气，类似于X形喷射形态。合成X射线图像揭示了多对喷射动力冲击和空腔。大规模的磁通量会积聚在$ \ rm SMBH $上，变得动态重要，并导致磁盘被磁性磁盘状态。 $ 2 \％$ $ 2 \％$的$ \ rm smbh $（$ \ dot {m} \ simeq2.4 \ simeq2.4 \ times10^{ - 3} m _ {\ odot} \，{\ rm yr yr}^{ - 1}^{ - 1} $ for m87*} $ for m87*）$ for m87*）$ efferes twils $ eff $ eff $ eff $ eff。这些喷气机足够强大（$ p _ {\ rm jets} \ simeq2 \ simeq2 \ times10^{44} \，{\ rm erg \，s}^{ - 1} $
X-shaped radio galaxies (XRGs) produce misaligned X-shaped jet pairs and make up $\lesssim10\%$ of radio galaxies. XRGs are thought to emerge in galaxies featuring a binary supermassive black hole ($\rm SMBH$), $\rm SMBH$ merger, or large-scale ambient medium asymmetry. We demonstrate that XRG morphology can naturally form without such special, preexisting conditions. Our 3D general-relativistic magnetohydrodynamic (GRMHD) simulation for the first time follows magnetized rotating gas from outside the $\rm SMBH$ sphere of influence of radius $R_{\rm B}$ to the $\rm SMBH$ of gravitational radius $R_{\rm g}$, at the largest scale separation $R_{\rm B}/R_{\rm g} = 10^3$ to date. Initially, our axisymmetric system of constant-density hot gas contains weak vertical magnetic field and rotates in an equatorial plane of a rapidly spinning $\rm SMBH$. We seed the gas with small-scale $2\%$-level pressure perturbations. Infalling gas forms an accretion disk, and the $\rm SMBH$ launches relativistically-magnetized collimated jets reaching well outside $R_{\rm B}$. Under the pressure of the infalling gas, the jets intermittently turn on and off, erratically wobble, and inflate pairs of cavities in different directions, resembling an X-shaped jet morphology. Synthetic X-ray images reveal multiple pairs of jet-powered shocks and cavities. Large-scale magnetic flux accumulates on the $\rm SMBH$, becomes dynamically important, and leads to a magnetically arrested disk state. The $\rm SMBH$ accretes at $2\%$ of the Bondi rate ($\dot{M}\simeq2.4\times10^{-3}M_{\odot}\,{\rm yr}^{-1}$ for M87*), and launches twin jets at $η=150\%$ efficiency. These jets are powerful enough ($P_{\rm jets}\simeq2\times10^{44}\,{\rm erg\,s}^{-1}$) to escape along the spin axis and end the short-lived jets state whose transient nature can account for the rarity of XRGs
